Network documents such as webpages may use a variety of fonts to convey style and enhance aesthetics. In many instances, a web browser or user agent with which the network documents are viewed might not be equipped to view the documents because the corresponding font or fonts are not loaded in the system. Accordingly, the user agent or device on which the user agent is operating may need to obtain the font through a network. Some font files may be large and thus require significant bandwidth for transmission. Font files generally include definition information for all glyphs regardless of whether the glyph is used by a network document. This represents a waste of bandwidth since data is being transmitted to a user agent device when that data is not needed.